It is known to employ bi-functional diorganosilane compounds for the modification of silicones. For this purpose, those compounds have recently acquired particular interest which contain in the molecule as organo component, in addition to a non-reactive radical such as alkyl cycloalkyl, a radical which comprises a key atom, preferably a chlorine atom, for the introduction of functional groups. The introduction of the desired functional groups may be effected after incorporation of the molecule into siloxane chains or also after esterification of the silicon-functional radical of the starting compound.